Metal sheet piling



Patented Mar. 6, 1928.-

PATENT OFFICE.

mr. PAEL, or- EEDELBERG, GERMANY.

METAL SHEET PILING.

Application filed. December 31, 1925, Serial No. 78,611, and in Germany December?, 1925. i

An important point in the Construction of sheet piling is the interconnection or interlocking of the individual pile members because, although the joints must be as nearly watertight as possible, they must cause a minimum of friction during the operation of ramming.

Now, in rolling the members, it is'practically impossible to make the jointing surfaces so mathematically level as to ensure accurate surface-contact when the members are assembled. Difiiculties therefore arise in ramming, since the members of the piling lock together in some places whereas in others there is too much free play, so that effective connection is altogether impossible. The resent invention obviates these drawbacks y applyng the principle of point contact or linear contact.

A typical embodiment of metal sheet pil ing in accordance with this principle is illustrated on the accompanying drawing whereom- F ig. 1 is a fragmentary plan, partly in section, of the piling; and Fig. 2 is a section, to a larger scale, of one of the looking joints.

Each locking joint is formed with concave or recessed walls, as shown, whereby cavities a, b, c are produced and contact occurs only at the points d, e, f, g. As a re sult of the cavities, the pile members fit e together, that is, can be rammed, easily. On

the other hand, an efiicient joint' is always obtained, and the members cannot twist out of engagement.

The cavities fill np-with compressed soll, or the like, in the ramming-operation, and this material forms a packing. When ramming in water, clay or like material can be applied on the side facing the water, and will be flushed into the leaky places by the 'eddies The shape of the cavities causes differences in the rate of flow, thus favouring the operation.

The stress on the joint will diminish with the friction, that is with the resistance set up in penetrating the ground, and therefore in ramming. In order to obtain the most favourable relation between thickness of material and Capacity to withstand resistance pressure of the ground, it is advisable, when the herein described connecting means are enployed, to replace the usual sheet .pile members by light steel members of increased strength and higher elongation limit, such as material containing, for example, 0.25- 030% C, 0.7 0.8% Mn, and traces of Si, the sulphur and -phosphorus content being normal. Such material does not cost appreciably more than ordinary mild steel, but is better adapted to stand ramnng and more easily transported, being stronger and, lighter. i

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 2- 1. Metal sheet piling eomprising individual pile members, interlocking jointing members on the inner edges of adjacent pile members having rigidly engaged portons for preventing a 'relative rotation of the pile members, the rigidly engaged portions having concaved surfaces facing each other in such a manner that the rigidly engaged portions of the j ointing members inter-looking each other have a linear contact throughout.

2. Metal sheet piling as claimed in claim 1, wherein the jointing members on the pile members include double bent fianges with' recessed contact surfaces at the bends of the fianges, and the fianges of one member when interlocked with the flanges of the adjacent member forming cavities in the interlocked oint.

3. Metal sheet piling as claimed in claim 1, wherein the jointing members include double bent flanges formed integral with the 'iadjacent members, the outerpart of each double flange being substantially triangular in section, and the other part of sad flange having inner walls, substantiallyas and for the purposes set forth.

In testimony whereof I afix my signature.

KARL PAHL. 

